Programming Tutorials and Coding Guides - Page 21

Find top CPU and memory consuming processes on Linux with ps, top, sar, and pidstat; sample output after controlled stress; Bash scripts that append metrics to a file and ideas for email alerts.

Bash patterns to see if a string contains a substring or character, if it is only digits, if it starts with a prefix, and how [[ =~ ]] and globs differ— with quoting, empty-string gotchas, and a short locale note.

Bash trap Ctrl+C (SIGINT): linux ctrl c signal basics, trap INT and trap ctrl-c patterns, ignore with trap empty string, EXIT cleanup, quoting pitfalls, and subshell vs child-process behavior.

Bash until vs while using exit status: bash until loop runs while a command fails, while loop bash runs while it succeeds. Examples for counters, wait until ready, and while read line-by-line.

Bash multiple arguments with positional parameters, bash pass all arguments via "$@", bash pass multiple arguments to a function, forwarding to another script, and bash pass function over SSH with typeset -f or declare …

Bash increment variable and bash add 1 to variable with $(( )), ((++)), bash increment variable in loop (for/while), bash increment counter patterns, let, and post vs pre-increment pitfalls.

Bash format number with commas using printf thousands grouping, LC_NUMERIC and GNU numfmt, plus a pure Bash comma formatter for integers and decimals. Covers locale (en_US vs en_IN), C/POSIX limits, and readable output …

How await works in JavaScript: javascript await, js await, async await javascript, await promise inside async functions, sequential vs Promise.all concurrency, try/catch on rejections, await on non-promises, top level …

JavaScript factory pattern and factory functions: return plain objects, pick implementations by input, constructor-based factories, ES6 class factories, closure privacy, and async factories—with Node-tested output.

Nested loops in Java: nested for, while, and do-while (including mixed loops), Scanner menu example, labeled break, and complexity. Runnable examples with OpenJDK 17-tested output.

Learn how to write, append, and create files in Golang using os.WriteFile and os.OpenFile. This practical guide covers file writing, appending data, creating files if not exists, flags explanation, real-world examples, …

Learn Golang generics with practical examples including generic functions, structs, interfaces, and JSON parsing. This guide explains type parameters, constraints, real-world use cases, and common errors to help you …

Learn how to implement optional parameters in Golang using variadic functions, struct-based patterns, and pointer parameters. This guide explains why Go does not support default values and shows practical workarounds …

Learn how to use if, else if, and else statements in Golang with practical examples. This guide covers multiple conditions, logical operators (AND, OR, NOT), one-line if statements, real-world use cases, and best …

Learn how to read files in Golang using os.ReadFile, bufio.Scanner, and bufio.Reader. This guide covers reading entire files, line-by-line processing, handling large files efficiently, and common errors with practical …

Learn how to read files in Golang with timeout handling using select, time.After, and context.WithTimeout. This guide covers reading files line by line, in chunks, handling large files, fixing bufio.Scanner errors, and …

Learn how to implement JWT authentication in Golang using Gin and PostgreSQL. This step-by-step guide covers user signup, login, JWT token generation, middleware validation, REST API usage, and common errors for building …

Learn how to configure and use pytest logging effectively. This guide covers setting log levels, enabling live logs, using log_cli and caplog, fixing logs not showing, logging to file, and advanced configurations. …

Learn how to add elements to a set in Python using add() and update() methods. This guide covers adding single and multiple elements, handling duplicates, common mistakes like append() and insert(), and real-world use …

Learn how to compare strings in Python with practical examples. This guide covers string equality, case-insensitive comparison, substring matching, lexicographic comparison, character-by-character comparison, and …

Learn how to use floor() in Python with practical examples. Understand math.floor(), differences between floor vs int vs round, handling negative numbers, Pandas and NumPy usage, and common errors. Includes syntax, …

Learn how to fix the "ValueError: setting an array element with a sequence" in Python and NumPy. Understand inhomogeneous shape errors, causes, real examples, and step-by-step solutions to resolve array shape mismatch …

Learn how to pass arguments to npm scripts using double dash (--) and without it. Includes real examples, npm_config usage, environment variables, and best practices for Node.js scripts.

Learn Python regex (regular expressions) with practical examples, cheat sheet, and real-world use cases. Understand re module functions like search, match, findall, sub, and split with beginner-friendly explanations and …

Learn how to uninstall Golang (Go compiler) on Linux, macOS, and Windows. This guide explains how to remove Go installed using tarball archives, package managers, Homebrew, or installers, including cleaning environment …

Learn the differences between arrays and collections in Java with practical examples. This guide explains how to create arrays, initialize lists, print arrays, determine collection size, and work with common Java …

Learn how to use Python os.path.join() to safely combine file and directory paths across operating systems. This tutorial explains syntax, examples, multiple arguments, return values, and common use cases such as joining …

Learn how to generate UUID in Node.js using the uuid package, crypto module, nanoid, and other methods. This guide explains UUID versions, NodeJS UUID generation examples, and best practices for creating unique IDs in …

Learn how to use the enhanced for loop in Java (also known as the for-each loop) to iterate over arrays, lists, sets, and map entries. This guide explains syntax, practical examples, limitations, comparisons with …

Compare the best IDEs and editors for Go development: VS Code, GoLand, Neovim, Zed, LiteIDE, Sublime Text, and Emacs—use cases, trade-offs, setup checklist, and legacy tools to avoid.